In 1985, I received a patent for a machine called a "POTHOLE PATCHER" which provided a cold mixed asphaltic concrete paving material, U.S. Pat. No. 4,511,284. This machine mixes, fills and compacts "potholes" with asphaltic concrete paving material. It has a roller on the front end which is lowered to the desired depth of spread and as the machine rolled forward over the patch, it was spread out and smoothed to the desired thickness. After the pass to spread out and smooth the patch, the roller is then lowered further which raised the front end of the machine off the ground and the machine is put in reverse and the front roller then thoroughly compacts the paving mixture as the machine and roller backs over the patch. This machine worked very well for small "potholes" but we wanted to make a larger machine for full width highway paving using the cold mixed process. We found the cold mixed, sticky, asphalt paving material was next to impossible to smooth out and spread in preparation for rolling and compacting in large amounts. We tried many types of conventional asphalt spreading devices, both heated and unheated. None worked very well and most of the time the sticky cold mixed asphalt paving material would build-up in front of the screed and just slide along and not spread out. Cold mixed asphaltic concrete paving material has much the same characteristics as bread dough. Bread dough cannot be spread with a knife or blade, it must be spread and smoothed out with a "rolling pin". After building and trying many types of spreading devices, which did not work well, I finally hit upon the idea of putting an adjustable "rolling screed" in a spreader box followed by a compression roll. This works similar to our "Pothole Patcher" which employed a forward pass as a screed roll and a reverse pass as a compression roll. Additional pressure applied from the mixer vehicle aids complete compaction and reduces or eliminates the need for further final roadway compacting.
My new invention is called the "Rolling Screed" Spreader Box. The "Rolling Screed" Spreader Box does a very smooth job of spreading cold mixed asphaltic concrete paving material and has been improved and adapted also for cement concrete paving material as well.